Abstract: A composite material includes an SiC porous ceramic sintered body, which is formed by preliminarily sintering a porous body, having a coefficient of thermal expansion lower than the coefficient of thermal expansion of copper to construct a network therein. A copper alloy impregnating the porous ceramic sintered body includes copper and one or more additive elements which are prepared to impart a coefficient of thermal conductivity of 160 W/mK or higher to the composite material. The additive elements include up to 5% of at least one element selected from Be, Al, Si, Mg, Ti, Ni, Bi, Te, Zn, Pb, Sn, and mish metal, and also contain unavoidable impurities and gas components.

Abstract: Techniques to bond two or more smaller bodies or subunits to produce a unitary SiC composite structure extend the capabilities of reaction-bonded silicon carbide, for example, by making possible the fabrication of complex shapes. In a first aspect of the present invention, two or more preforms are bonded together with a binder material that imparts at least strength sufficient for handling during subsequent thermal processing. In a second aspect of the present invention, instead of providing the subunits to be bonded in the form of preforms, the subunits may be dense, SiC composite bodies, e.g., RBSC bodies. In each of the above embodiments, a preferable means for bonding two or more subunits combines aspects of adhesive and mechanical locking characteristics. One way to accomplish this objective is to incorporate a mechanical locking feature to the joining means, e.g., a “keyway” feature.

Abstract: A method of continuously producing a non-oxide ceramic formed of a metal constituent and a non-metal constituent. A salt of the metal constituent and a compound of the non-metal constituent and a compound of the non-metal constituent are introduced into a liquid alkali metal or a liquid alkaline earth metal or mixtures to react the constituents substantially submerged in the liquid metal to form ceramic particles. The liquid metal is present in excess of the stoichiometric amount necessary to convert the constituents into ceramic particles to absorb the heat of reaction to maintain the temperature of the ceramic particles below the sintering temperature. Ceramic particles made by the method are part of the invention.

Abstract: A method for extracting silica from herbaceous plant capable of extracting high purity amorphous silica from seed shell of various herbaceous plants is provided. The method includes carbonizing a herbaceous plant and pulverizing a carbide of the plant to a size of at least 50 mesh, adding at least 5% (w/w) aqueous alkaline solution based on 100 weight percents of the carbide, leaving a reactant of the solution and the carbide for 1 hour at about 45° C. and filtering the reactant, slowly heating the reactant to a predetermined temperature, dropping sulfuric acid to the reactant at the predetermined temperature until the sulfuric acid is neutralized, and evaporating and drying the reactant to produce silica.

Abstract: A continuous flow chemical reaction apparatus comprises a tubular reactor having a length and having a first fluid reactant inlet at a first end and a product outlet at a second end, said tubular reactor having a central tube/interior conduit extending lengthwise within said tubular reaction zone, said conduit having at least one injector within the length of said conduit, said injector capable of introducing a controlled amount of a second fluid reactant into said tubular reactor.

Abstract: A chemical vapor deposited, &bgr; phase polycrystalline silicon carbide having a high thermal conductivity and reduced stacking faults. The silicon carbide is synthesized under specific conditions using hydrogen gas and methyltrichlorosilane gas as reactants. The thermal conductivity of the silicon carbide is sufficiently high such that it can be employed as parts of apparatus and components of electrical devices where a high heat load is generated. Such components may include active thermoelectric coolers, heat sinks and fans.

Abstract: This invention relates to a method for preparing nanometer SiC material using nanometer-grade or micron-grade commercial SiC with different shapes, sizes as raw material. The raw materials and catalysts are put into heating device, which is pumped beforehand. Inert gas is let into the heating device as protective gas. The materials and catalysts then will be heated to temperature of 1300˜2000° C., and the temperature preserved for a certain period. The nanorod or nanowire produced can be used in the research and development for SiC photoelectric devices, especially for nanometer photoelectric devices and field emission electron sources. This method features simple operation, low cost, and high yield.

Abstract: The present invention discloses methods for the processing of commercially obtained silicon carbide particles to enhance the nucleic acid binding properties of the silicon carbide. The methods use a variety of chemical washes which may also use high temperature treatment under gentle boiling followed by cooling and allowing the particles to settle, and milling to obtain the desired grit size.

Abstract: Method for producing discontinuous silicon carbide fibers, useful as heating elements in a low-energy microwave field, from discontinuous carbonized cotton fibers employing an admixture of carbonized cotton fibers, a metal salt promoter, calcium oxalate monohydrate, and low-density silicon dioxide. The admixture, in a dry state, is introduced into a preheated oven at about 1450 to 1750 degrees C. for between about one and five hours. Silicon carbide fibers and a sheet formed from the fibers are disclosed.

Abstract: Methods for producing molybdenum carbide. An embodiment of the method may comprise heating a precursor material in a first heating zone in the presence of a reducing gas and a carbonizing gas, the first heating zone having a first temperature. Moving the precursor material into a second heating zone to form the molybdenum carbide from the precursor material, the second heating zone having a second temperature, the second temperature being at least 100° C. hotter than the first temperature.

Abstract: A method of producing a silicon carbide powder comprising sintering a mixture containing at least a silicon source and a carbon source wherein the carbon source is a xylene-based resin. Preferable are an embodiment in which the above-mentioned silicon source is an alkoxysilane compound, an embodiment in which the above-mentioned alkoxysilane compound is selected from an ethoxysilane oligomer and an ethoxysilane polymer, an embodiment in which the above-mentioned mixture is obtained by adding an acid to a silicon source, then, by adding a carbon source, and other embodiments. A silicon carbide powder produced by the above-mentioned method of producing a silicon carbide powder wherein the nitrogen content is 100 ppm or less is preferable. A sintered silicon carbide obtained by sintering the above-mentioned silicon carbide powder wherein the volume resistivity is 1×100 &OHgr;·cm or more.

Abstract: A fine &bgr;-silicon carbide powder is prepared by impregnating graphite with an organosilicon compound selected from crosslinkable silanes and siloxanes, causing the organosilicon compound to crosslink within the graphite, and heating at 1,300° C. or higher in an inert gas stream for reaction. Using only low-temperature heat treatment in air and high-temperature heat treatment in inert gas, the invention enables industrial, economical manufacture of fine silicon carbide powder in a stable manner.

Abstract: A non-single crystalline semiconductor material includes coordinatively irregular structures characterized by distorted chemical bonding, reduced dimensionality and novel electronic properties. A process for forming the material permits variation of the size, concentration and spatial distribution of coordinatively irregular structures. The electronic properties of the material can be changed by controlling the characteristics of the coordinatively irregular structures.

Abstract: A method for the manufacture of a structure from a carbide of a group IIa, group IIIa, group IVa, group IVb, group Vb, group VIb, group VIIb or group VIIIb carbon reactive element including the steps of: mixing the element with the carbon; and heating the carbon and the element to melt the element so that it reacts with the carbon to form the carbide; wherein, the carbon and element are heated by means of electromagnetic radiation having a frequency below the infrared spectrum. The method does not waste energy by unnecessary heating of the furnace or surrounding mold. The mold itself may be more stable because it is only heated by hot contained material and not by other sources of heat. Resulting formed products are not a sintered product and may approach one hundred percent of theoretical density. The carbon may be in the form of a powder that is mixed with the element or may be a porous carbon structure such as a graphite fiber mat or sheet into which the carbon reactive element is melted.

Abstract: A process for forming a silicon carbide structure includes molding by compression a mixture of a silicon precursor powder and a cross-linking thermoset resin to form a rigid structure, carbonizing the rigid structure, and forming a silicon carbide structure by heating the carbonized rigid structure at a temperature sufficient to allow carbon and silicon in the structure to react to form silicon carbide.

Abstract: The present invention provides: a fabrication method of a silicon carbide sintered body, including a step of fabricating a mixed powder slurry by dissolving or dispersing silicon carbide powder, at least one organic material composed of a nitrogen source, and at least one organic material composed of a carbon source or carbon powder in a solvent, a step of fabricating a green body by pouring the mixed powder slurry into a mold and drying and a step of filling pores in the green body by immersing the green body in high purity metallic silicon that has been heated to 1450 to 1700° C. in a vacuum atmosphere or inert gas atmosphere and melted, and generating silicon carbide by reacting silicon sucked up into the pores in the green body by capillary action with free carbon in the green body; and a silicon carbide sintered body obtained by a reaction sintering method, having a density of 2.90 g/cm3 or more and a volume resistivity of 100 &OHgr;·cm or less, and containing nitrogen at 150 ppm or more.

Abstract: A silicon carbide-based porous material containing silicon carbide particles (1) as an aggregate and metallic silicon (2), wherein the average particle diameter of the silicon carbide-based porous material is at least 0.25 time the average particle diameter of the silicon carbide particles (1), or the contact angle between the silicon carbide particles (1) and the metallic silicon (2) is acute, or a large number of secondary texture particles each formed by contact of at least four silicon carbide particles (1) with one metallic silicon (2) are bonded to each other to form a porous structure. This silicon carbide-based porous material can be sintered, in its production, at a relatively low firing temperature and, therefore, can be provided at a low production cost, at a high yield and at a low product cost.

Abstract: Silicon carbide fibers are produced by mixing discontinuous isotropic carbon fibers with a silica source and exposing the mixture to a temperature of from about 1450° C. to about 1800° C. The silicon carbide fibers are essentially devoid of whiskers have excellent resistance to heating and excellent response to microwave energy, and can readily be formed into a ceramic medium employing conventional ceramic technology. The fibers also may be used for plastic and metal reinforcement.

Abstract: A high purity silicon carbide powder, a production method thereof, and a high purity silicon carbide sintered body are provided. The silicon carbide powder contains impurity elements, each of the impurity elements being contained in an amount of at most 0.01 ppm; the production method of silicon carbide powder includes a burning step, in which amounts of carbon monoxide generated during burning are detected and temperature adjustments are controlled in accordance with the detected amounts, and a heat treatment step, in which silicon carbide powder obtained in the burning step is heat-treated in a vacuum atmosphere; and the silicon carbide sintered body is formed by sintering silicon carbide powder.

Abstract: A method of making a ceramic article includes the providing a member. The member includes a cellulose-based material. The cellulose-based material is carbonized to carbon. At least a portion of the member is covered with silica sand after carbonization. At least a portion of the carbon of said member, which has been carbonized, is converted to silicon carbide.

Abstract: A process for producing a honeycomb structure, which comprises adding water to a mixed raw material of a raw material powder and a binder, kneading the mixture to obtain a plastic mixture, molding the plastic mixture into a honeycomb shape to obtain a green honeycomb structure, drying the structure by a step including hot-air drying, and firing the resulting dried honeycomb structure, wherein the binder contains hydroxypropyl methyl cellulose as a major component. The process can produce a crack-free high-quality honeycomb structure rapidly at a low cost.

Abstract: A ceramic bearing ball in which at least a portion of a constituent ceramic is formed of an electrically conductive inorganic compound phase, whereby a proper electrical conductivity is imparted to the ceramic. Thus, electrifying of a bearing ball is prevented or effectively suppressed. This prevents the problem involved in production of balls of small diameter wherein such balls adhere to an apparatus (e.g., a container) during production thereof, thus hindering smooth progress of the production process. In addition, when ceramic balls are used in precision electronic equipment, such as a hard disk drive of a computer, which is operated at high rotational speed, adhesion of foreign substance due to electrification of the balls, and resultant generation of abnormal noise or vibration can be prevented or effectively suppressed.

Abstract: A method of producing very high purity fine powders of oxides, carbides, nitrides, borides, chalcogenides, metals, and alloys. The purity of powders produced by the method exceeds 99.9%, preferably 99.999%, more preferably 99.99999%, and most preferably 99.9999999%. Fine powders produced are of size less than 100 microns, preferably less than 10 micron, more preferably less than 1 micron, and most preferably less than 100 nanometers. Methods for producing such powders in high volume, low-cost, and reproducible quality are also outlined. The very high purity, fine powders are envisioned to be useful in various applications such as biomedical, sensor, electronic, electrical, photonic, thermal, piezo, magnetic, catalytic and electrochemical products.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A fine &bgr;-silicon carbide powder is prepared by impregnating graphite with an organosilicon compound selected from crosslinkable silanes and siloxanes, causing the organosilicon compound to crosslink within the graphite, and heating at 1,300° C. or higher in an inert gas stream for reaction. Using only low-temperature heat treatment in air and high-temperature heat treatment in inert gas, the invention enables industrial, economical manufacture of fine silicon carbide powder in a stable manner.

Abstract: A composition useful for making in-situ silicon carbide whiskers and fibers in an inorganic composite matrix selected from silicon carbide carbon and carbon composite matrix, wherein the said composition comprises: Natural Fiber (1.6-6.5 Wt %); TetraEthyl Orthosilicate (10.4-42 Wt %); Phenolic Resin (38-73.5 Wt %); Curing agent (4.2-11 Wt %); Optionally, Silicon Carbide (9.4-12 Wt %); Organic Solvent (requisite amount to dissolve the Phenolic resin). The fiber preferably is a natural fiber selected from the group consisting of jute, sisal, hem and other natural fiber having cellulosic or hemicellulosic constituent at its backbone. The curing agent preferably is selected from hexamine, para toluenesulphonic acid and para formaldehyde, most preferably hexamine. The molecular weight of phenolic resin preferably is in the range of 450-700, and the organic solvent preferably is selected from methanol, toluene and benzene.

Abstract: A low defect (e.g., dislocation and micropipe) density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, grown using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocations and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.

Abstract: In a single crystal SiC composite material for producing a semiconductor device, and a method of producing the same according to the invention, a single crystal SiC film which is produced on an Si substrate by the heteroepitaxial growth method and obtained by removing the Si substrate, is stacked and bonded via a film-like SiO2 layer onto the surface of a polycrystalline plate consisting of Si and C atoms in a closely contacted manner forming thereby a stacked composite member. The stacked composite member is then heat-treated, whereby single crystal SiC in which the crystal is transformed in the same orientation as the single crystal of the single crystal SiC film is integrally grown on the polycrystalline plate. The thickness and the strength which are requested for producing a semiconductor device can be ensured, and lattice defects and micropipe defects seldom occur, so that an accurate and high-quality semiconductor device can be produced.

Abstract: A nanostructure based material is capable of accepting-and reacting with an alkali metal such as lithium. The material exhibits a reversible capacity ranging from at least approximately 900 mAh/g-1,500 mAh/g. The high capacity of the material makes it attractive for a number of applications, such as a battery electrode material.

Abstract: Method for producing discontinuous silicon carbide fibers, useful as heating elements in a low-energy microwave field, from discontinuous carbonized cotton fibers employing an admixture of carbonized cotton fibers, a metal salt promoter, calcium oxalate monohydrate, and low-density silicon dioxide. The admixture, in a dry state, is introduced into a preheated oven at about 1450 to 1750 degrees C. for between about one and five hours. Silicon carbide fibers and a sheet formed from the fibers are disclosed.

Abstract: The invention relates to a process for the selective recovery of olefins from a mixture of gases by: a) bringing a gaseous mixture having olefins and hydrogen into contact with silver nitrate solution whereby the olefins are absorbed into the silver nitrate solution as a complex; b) separating the solution having complexed olefins from the non-absorbed gases; c) depressurising and heating the olefin complex solution from (b) so as to release the olefins from the complex and regenerate the silver nitrate solution; d) passing the regenerated silver nitrate solution through a bed containing silver oxide so as to maintain the pH value of the silver nitrate at between 3 and 6; and e) recycling the silver nitrate solution regenerated in (d) to step (a).

Abstract: The process includes the steps of combining silica with the spent pot liner in order to convert a majority of the spent pot liner into silicon carbide. Specifically, the silica reacts with carbon in the spent pot liner to form silicon carbide. In order to form the silicon carbide, the materials are heated, such as in an electric resistance heater. The formed silicon carbide is free of contaminants and can be used for many useful purposes.

Abstract: A highly resistive recrystallized silicon carbide having open pores, wherein layered carbons on the inner wall surfaces of said open pores are removed and a resistivity at room temperature of said recrystallized silicon carbide is not less than 10000 &OHgr;·cm.

Abstract: A nanostructure based material is capable of accepting and reacting with an alkali metal such as lithium. The material exhibits a reversible capacity ranging from at least approximately 900 mAh/g-1,500 mAh/g. The high capacity of the material makes it attractive for a number of applications, such as a battery electrode material.

Abstract: Silicon carbide having a resistivity of from 103 to 106 &OHgr;·cm and a powder X-ray diffraction peak intensity ratio of at least 0.005 as represented by Id1/Id2 where Id1 is the peak intensity in the vicinity of 2&thgr; being 34° and Id2 is the peak intensity in the vicinity of 2&thgr; being 36°.

Abstract: A chemical vapor deposited, p phase polycrystalline silicon carbide having a high thermal conductivity and reduced stacking faults. The silicon carbide is synthesized under specific conditions using hydrogen gas and methyltrichlorosilane gas as reactants. The thermal conductivity of the silicon carbide is sufficiently high such that it can be employed as parts of apparatus and components of electrical devices where a high heat load is generated. Such components may include active thermoelectric coolers, heat sinks and fans.

Abstract: Provided are SiC-C/C composite materials which have such characteristics as a suitable kinetic coefficient of friction a corrosion resistance in strongly oxidizing and corrosive environment, a creep resistance, and a spalling resistance, a high hardness, and are hardly oxidized or abraded even when exposed to high temperatures with keeping the excellent impact resistance and light weight of the C/C composites. Furthermore, molten metal pumps are provided from which components do not dissolve into the molten metal even when used in molten metal and have sufficient thermal impact resistance and oxidation resistance.

Abstract: A method of producing finely-divided particles of silicon carbide (SiC), by introducing into a furnace a crucible containing a layer of finely-divided particles of carbon and a layer of finely-divided particles of elemental silicon separated by a layer permeable to silicon vapor; subjecting the interior of the furnace to a vacuum; and heating the crucible to a sufficiently high temperature for a sufficiently long period of time to vaporize and diffuse the silicon and to react the silicon vapor with the carbon particles to convert them to silicon carbide particles.

Abstract: This invention is a high strength, thermal shock resistant, high purity siliconized silicon carbide material made from siliconizing a converted graphite SiC body having at least 71 vol % silicon carbide therein.

Abstract: A method for preparing a carbon-containing composition is disclosed which comprises the steps of introducing, into a hot gas, a dispersion obtained by dispersing, in a decomposable carbon compound, a metal oxide and/or a metal compound which can be converted into the metal oxide by heating, to form a carbon-containing composition containing simple carbon and the corresponding metal oxide; and then collecting the formed carbon-containing composition. This carbon-containing composition is useful for the manufacture of a ceramic powder for sintering.

Abstract: A method of making a compound selected from metal and silicon carbides and nitrides includes the steps of providing a solution of a coal-derived material in a solvent, the coal-derived material having a composition, free of solvent, of 70 to 91 percent by mass of carbon, 2 to 6 percent by mass of hydrogen and 3 to 20 percent by mass of oxygen, and a source of an oxide of silicon or the metal, causing the coal-derived material in solution and the source of the oxide to interact, removing the solvent to form a precursor and heat treating the precursor to produce the compound.

Abstract: A nanostructure based material is capable of accepting and reacting with an alkali metal such as lithium. The material exhibits a reversible capacity ranging from at least approximately 900 mAh/g-1,500 mAh/g. The high capacity of the material makes it attractive for a number of applications, such as a battery electrode material.

Abstract: A formed SiC product having a low degree of light transmittance useful in a variety of heat resistant components such as equalizing rings, dummy wafers, and other components employed in semiconductor manufacturing facilities, and the manufacturing method thereof. The product is a CVD-formed SiC product prepared by growing a coating on a substrate with a CVD process and thereafter removing the substrate. The product is characterized by having at least one SiC layer with different grain characteristics located either on its surface or within the main structure, and having a light transmittance rate of 0.4% or less for the wavelength range from 300 to 2,500 nm, and 2.5% or less for the wavelength range exceeding 2,500 nm. The method for manufacturing the formed SiC product is characterized by forming at least one SiC layer with different grain characteristics either on its surface or within the main structure provided by changing the CVD reaction conditions.

Abstract: A silicon carbide thin film is epitaxially grown by an MBE or the like method with silicon atoms 2 being maintained to be in excess of carbon atoms on a growth surface 1a of a silicon carbide crystal in a substrate 1. A silicon carbide substrate with a good crystallinity is thereby achieved at a low temperature with a good reproducibility. This crystal growth is possible at a low temperature of 1300° C. or lower, and the productions of a high-concentration doped film, a selectively grown film, and a grown film of a cubic silicon carbide on a hexagonal crystal are achieved. In crystallizing a cubic silicon carbide on a hexagonal crystal, the use of an off-cut surface inclined towards a <1{overscore (1)}00> direction is effective to prevent an occurrence of twin.

Abstract: A sublimation technique of growing silicon carbide single crystals, comprising a parallel arrangement, opposite each other, of the evaporating surface of a silicon carbide source (1) and the growing surface of at least one seed crystal (2) of a specified politype, to define a growth zone (4), and generation of a reduced pressure and an operating temperature field with an axial gradient in the direction from the seed crystal (2) towards the source (1), providing evaporation of silicon carbide of the source (1) and vapour-phase crystallization of silicon carbide on the growing surface of the seed crystal (2). The growth zone (4) is here sealed before the operating temperatures are reached therein, and the process is run with a solid solution of tantalum and silicon carbides in tantalum and their chemical compounds present in the growth zone (4). The material of the source (1) employed for implementing the sublimation technique of growing silicon carbide crystals is silison carbide ceramics.

Abstract: The present invention is to provide a production method of silicon carbide particles of high quality without generating a sulfur compound in the carbonizing and baking processes. More concretely, a production method of silicon carbide particles comprising a step of mixing at least one kind of a silicon compound, which is liquid at ordinary temperatures, an organic compound having a functional group, which generates carbon by heating and is liquid at ordinary temperatures, and a polymerization or crosslinking catalyst, which can homogeneously dissolve with the organic compound to obtain a mixture, a step of homogeneously solidifying the mixture to obtain solid matter, and a step of heating and baking the solid matter in a non-oxidizing atmosphere, wherein the catalyst is a compound consisting of carbon atoms, hydrogen atoms and oxygen atoms, and has a carboxyl group.

Abstract: This invention is a high strength, thermal shock resistant, high purity siliconized silicon carbide material made from siliconizing a converted graphite SiC body having at least 71 vol % silicon carbide therein.

Abstract: A method and an apparatus have been developed to grow beta-silicon carbide nanorods, and prepare patterned field-emitters using different kinds of chemical vapor deposition methods. The apparatus includes graphite powder as the carbon source, and silicon powder as silicon sources. Metal powders (Fe, Cr and/or Ni) are used as catalyst. Hydrogen was the only feeding gas to the system.

Abstract: According to the present invention, a complex (M) which is formed by growing a polycrystalline &bgr;-SiC plate 2 having a thickness of 10 &mgr;m or more on the surface of a single crystal &agr;-SiC base material 1 by the PVD method or the thermal CVD method is heat-treated at a temperature of the range of 1,650 to 2,400° C., whereby polycrystals of the polycrystalline cubic &bgr;-SiC plate 2 are transformed into a single crystal, and the single crystal oriented in the same direction as the crystal axis of the single crystal &agr;-SiC base material 1 is grown. As a result, single crystal SiC of high quality which is substantially free from micropipe defects and defects affected by the micropipe defects can be produced easily and efficiently.

Abstract: The invention relates to a silicon carbide or metal carbide foam to be used as a catalyst or catalyst support for the chemical or petrochemical industry or for silencers, as well as the process for producing the same. The foam is in the form of a three-dimensional network of interconnected cages, whose edge length is between 50 and 500 micrometres, whose density is between 0.03 and 0.1 g/cm3 and whose BET surface is between 20 and 100 m2/g. The carbide foam contains no more than 0.1% by weight residual metal and the size of the carbide crystallites is between 40 and 400 Angstroms. The production process consists of starting with a carbon foam, increasing its specific surface by an activation treatment using carbon dioxide and then contacting the thus activated foam with a volatile compound of the metal, whose carbide it is wished to obtain.